Voltage regulator



July 21, 1959 G. DIEPENHORST ETAL 2,

VOLTAGE REGULATOR Filed Jan. 7, 1957 a. D/EPENHORST,

T5 5. E MSIDUNENFELD.

INVENTORS. (5. C. 771: 7&0. BY 7Z:$ax4%rwu United States Patent VOLTAGEREGULATOR Gerald Diepenhorst, Romulus, and Marvin S. Dunenfeld, AnnArbor, Mich., assignors to Ford Motor Company, Dearborn, Mich., acorporation of Delaware Application January 7, 1957, Serial No. 632,779

8 Claims. (Cl. 200-102) This invention pertains to a voltage regulatorwhich is especially adaptable to a motor vehicle electrical system.

In the conventional voltage regulator there are three cores and threewindings in order to provide the generator from exceeding a maximumvoltage and current value and also to prevent the battery fromdischarging into the generator. With this invention the same functionsare performed but a core has been eliminated resulting in a space andcost saving.

This invention and its objects and advantages will be better understoodwhen a preferred embodiment is discussed in connection with the drawingsin which:

Figure 1 is a schematic drawing of the electrical circuit used in thepreferred embodiment; and

Figure 2 is an elevational partially broken away view of a core whichhas two windings and two switches connected therewith.

In Figure l is seen the circuit which makes possible the use of only twocores in a motor vehicle voltage regulating system while stillperforming the functions of a three core system. Connected between thearmature of generator 21 and field 22 is field limiting resistance 24which may have a value of 120 ohms for a 12 volt 38 ampere generator andthis resistance is bypassed by switches 27-1 and 29-1 which are openedrespectively by excessive voltage across shunt voltage relay 27 andexcessive current through series current winding 29. Resistance 31 whichmay be 50 ohms is connected between the field circuit and ground. Switch28-1 is closed by shunt voltage windings 28 when the armature voltage isequal to or greater than a predetermined voltage which may be between 12and 12.8 volts. It is seen that windings 28 and 29 are wound on core 32.Battery 23 is shown connected to relay 29 with the rest of the vehicleelectrical circuit not being shown.

Figure 2 illustrates a possible construction for having two windings onthe same core. Core 32 has wound about it voltage coil 28 which has manyturns of fine wire and about coil 28 is wound current coil 29 which hasa few turns of heavy wire. Hinged to core housing 36 through member '38is magnetic arm 37 which closes the contacts for switch 28-1. Member 38may be bimetallic so that during cold ambient temperatures switch 28-1will close later under a higher voltage than during a warmer ambienttemperature because higher voltages are needed in cold weather. Fastenedto arm 37 are contacts for switch 29-1 with the lower portion of thelower contact extending through opening 39 in arm 37. Contacts 29-1 arenormally closed with the lower contact being held by bimetallic hinge 41so that during cold ambient temperatures the generator field will haveresistance 24 thrown in at a higher current.

In the operation of this embodiment switch 28-1 re- 2,896,046 PatentedJuly 21, 1959 mains open until a minimum voltage has been developed bythe generator armature. By making this voltage higher than the batteryvoltage, battery discharge into the generator will be prevented. Theclosing of switch 28-1 is done by arm 37 being drawn downwardly by acertain value of the magnetic field of core 32 which is established bythe Winding of voltage coil 28. Now as the armature voltage and currentincrease above predetermined maximums which may be 15 volts and 30amperes switch 27-1 and/or 29-1 is opened putting resistance 24 into thefield circuit decreasing the generator output. Voltage relay coil 27 maybe of conventional design while current relay coil 29 is wound aboutvoltage coil 28 and when the combination of field strengths establishedby coils 28 and 29 reaches a predetermined value the lower contact ofswitch 29-1 which is connected to magnetic disc 33 is pulled away fromthe upper contact throwing in resistance 24 to the field circuit. Inthis embodiment the value at which the current will open switch 29-1will be 30 amperes at 15 volts and 32.5 amperes at 12 volts.

It will be understood that this invention is not to be limited to theexact construction shown and described, but that various changes andmodifications may be made without departing from the spirit and scope ofthe invention as defined in the appended claims.

What is claimed is:

1. In a voltage regulator that improvement comprising a core having twowindings and two switches, a first switch being hinged at one end ofsaid core and a second switch being hinged to said first switch, saidfirst switch defining a flux path opening, a portion of said secondswitch extending through said opening so that after said Winding andcore have established a predetermined field said second switch will beopened.

2. In a combined cutout relay and current regulating mechanism wherein acutout relay coil and a current coil are wound on a single magnetic corethat improvement comprising a cutout contact actuating armature operablypositioned in the flux path of said core, said contact actuatingarmature defining an opening therein within the region of said fluxpath, a current-limiting contact actuating armature mounted on saidfirst-named armature and positioned over said opening to be actuated byflux through said opening.

3. The mechanism of claim 2 wherein said secondnamed armature isactuated by a substantially increased flux density over the amountrequired to actuate the first-named armature.

4. In a magnetic relay having a wire wound core, that improvementcomprising a first contact carrying armature operably positioned in theflux path of said core, said first armature defining an opening thereinwithin the region of said flux path, a second contact carrying armaturepositioned over said opening to be operated by flux from said corethrough said opening.

5. The device as in claim 4 wherein said second armature is carried bysaid first armature.

6. The device as in claim 4 wherein said second armature is bimetallic.

7. The device as in claim 4 wherein said second armature includes aportion extending into said opening.

8. In a combined cutout relay and current-regulating mechanism wherein acutout relay coil and a current coil are wound on a single magnetic corethat improvement comprising a cutout contact actuating armature operablypositioned in the flux path of said core, said contact actuatingarmature defining an opening therein in the region of said flux path,and a current-limiting contact actuating armature positioned over saidopening to be actuated by flux therethrough.

References Cited in the file of this patent UNITED STATES PATENTS1,247,649 Doman Nov. 27, 1917 10

